Effects of β-cyclodextrin-dextran polymer on stability properties of trypsin

Dextran modified with the mono-6-pentylene-diamino-6-deoxy-beta-cyclodextrin derivative was evaluated as a thermoprotectant additive for trypsin. The optimum temperature for trypsin activity was increased by 7degreesC in the presence of this polymer. The enzyme thermo-stability was increased from 48.5 to 64degreesC over 10 min of incubation, and the activation free energy of thermoinactivation at 50degreesC was increased by 4.1 kJ/mol in the presence of the additive. Trypsin was 6-fold more resistant to autolytic inactivation at alkaline pH in the presence of the polymer. (C) 2003 Wiley Periodicals, Inc.